The subject matter disclosed herein relates to aftertreatment systems for engine systems. Specifically, the subject matter described below relates to systems and methods for using transport time delay to estimate engine aftertreatment system characteristics.
Engine systems provide power for a variety of application, such as oil and gas processing systems, commercial and industrial buildings, and vehicles. Many engine systems include or are coupled to a control system that oversees the operation of the engine system. The control system may improve efficiency of the engine system, and provide other functionality. For example, the control system may improve the efficiency of the engine system by controlling the air-to-fuel ratio of the engine, which represents the amount of air provided to the engine relative to the amount of fuel provided to the engine. Depending on desired applications, the control system may try to keep the air-to-fuel ratio near stoichiometry, which is the ideal ratio at which all of the fuel is burned using all of the available oxygen. Other applications may keep the air-to-fuel ratio lean (i.e., excess air) or in a range between rich (i.e., excess fuel) and lean.
As will be appreciated, engine systems produce exhaust gases as a result of burning fuel; and the type of exhaust gases emitted may depend in part on the type and amount of fuel provided to the engine system. Many industries and jurisdictions (e.g., coal-burning plants, federal and state governments, etc.) may have regulations and restrictions specifying the types and amounts of exhaust gases that different engine systems are permitted to emit.
To comply with regulations and restrictions, engine systems may also include an aftertreatment system coupled to the engine, which may include a catalytic converter system. The catalytic converter system receives the exhaust gases from the engine system and substantially converts the exhaust gases into other types of gases permitted by regulations and restrictions, and then exhaust conduits release the resultant exhaust into the atmosphere. The performance of the aftertreatment system may impact the performance of the engine, and vice versa. It would be beneficial to improve the performance of the engine and aftertreatment systems.